Extended Type Design.

[Andrei Alexandrescu (See Website For Email)]

kris wrote:
> Andrei Alexandrescu (See Website For Email) wrote:
>> Bill Baxter wrote:
>>
>>> Andrei Alexandrescu (See Website For Email) wrote:
>>>
>>>> Benji Smith wrote:
>>>
>>>
>>>>> I reiterate: "const" and "readonly" are the way to go. (Methods 
>>>>> which promise not to modify the values of their parameters should 
>>>>> use "readonly" rather than "const" in their method signatures.)
>>>>
>>>>
>>>> This makes const gratuitously incompatible to C++'s const, and 
>>>> (worse) also adds a keyword that's its equivalent. I don't think 
>>>> this can fly.
>>>
>>>
>>> What about 'immutable' for 'really can't change'/'superconst', and 
>>> const can stay as is?
>>
>>
>> I like it, and suggested it at a point. Walter said that it's bad 
>> marketing to define keywords in terms of a negative.
> 
> So, "invariant" is already a keyword ... what about that?
> 
> "Invariant" is currently used to stipulate a condition that must remain 
> constant (or true) for the extent of the enclosing/relevant scope. Right 
> now, it is used within a class only, but the semantics could presumably 
> extend elsewhere too:
> 
> invariant int * p = &x;
> 
> void myFunc (invariant char[] arg) {}
> 
> in both these cases, the "invariance" should remain for the extent of 
> the relevant scope?

I completely missed that one. I think it's a good idea to look into it 
as a candidate for a qualifier name. Thank you.

Andrei